Collin County, TX: flood risk, in FEMA's own numbers
On FEMA's National Risk Index, Collin County scores at the 96.8th percentile for flood hazard, rated "Relatively High" — well above the national norm for flood hazard. The hazard here is driven by inland rivers and flash flooding rather than the coast — FEMA's model puts a flood event here at about 2.1 times a year. This describes the county, not any one street — FEMA only publishes exact parcel zones through a live map service.
Who actually carries the flood insurance FEMA requires
Homes with a federally backed mortgage inside Collin County's mapped high-risk flood zone (the Special Flood Hazard Area, or SFHA) are legally required to carry an NFIP flood policy. In practice, 33.7% of them do — 312 active policies against 927 structures FEMA counts in that zone, leaving a real compliance gap. Looking beyond the mandated zone, 0.5% of all residential structures in Collin County carry flood coverage voluntarily or otherwise — relevant because most NFIP claims nationally come from outside the mapped SFHA.
Where Collin County ranks
Among the 3144 US counties FEMA scores for flood hazard, Collin County ranks 109 — 1 being the highest hazard nationally — and 35 by population among all 3144 counties covered here, where 1 is the largest. Collin County, Texas covers 841.513 square miles and counts roughly 1,254,658 residents.
Checking a specific address in Collin County
FEMA counts 300,712 residential structures in Collin County overall, 1,451 of them carrying some form of NFIP coverage — but a lender or insurer cares about one parcel, not that county total.
Where Collin County's figures come from
Every figure on this page traces to a named FEMA dataset, documented in the methodology guide. If you're unsure why any of this insurance requirement exists at all, the SFHA explainer covers it from first principles.